This is a proposal for a three-year renewal of a longitudinal program project on children of schizophrenic, depressed, or normal parents that has been ongoing since 1971. Major goals of the study have been concerned with the identification of early indicators of a liability to the development of schizophrenia or schizophrenia spectrum disorders or affective disorders. Two independent samples, each consisting of groups of children at risk for these disorders and a group at low risk for mental illness, are being followed until the subjects reach young adulthood to enable the investigators to trace the development of the subjects over a period of years and to relate psychobiological (i.e., attention and information processing, neuromotor functioning, and psychophysiological data) and behavioral variables studied in childhood to psychopathology emerging in adulthood. Sample A subjects have recently been examined (for the fourth time) in early adulthood. It is planned to conduct a fourth round of examinations on Sample B subjects in young adulthood, comparable to the recent assessment of Sample A. Further aims of the core project are to complete diagnostic ratings of psychiatric interviews conducted in the third examination of Sample B, to obtain final diagnostic assessments from a panel of three independent judges who will review lifetime data on the subjects blind with respect to parents' diagnoses, and to complete analyses of the data collected over the course of the entire study, including longitudinal analyses and cross-sample comparisons. Three subprojects are also proposed; each subproject will extend the data collection to the families of the main subjects in Sample A and Sample B. In Subproject l, personality disorder interviews will be conducted with the subjects and their nonpsychotic parents (spouses of patients or parents of the normal comparison subjects) to clarify the nature of spectrum disorders. In Subproject 2, family history interviews will be conducted with as many family members as possible to complete information needed for genetic analyses. In Subproject 3, siblings of the main subjects will be given the same clinical assessment battery as is administered to the main subjects at the time of their fourth round of examinations.